From patchwork Thu Feb 12 12:21:15 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Nan X-Patchwork-Id: 5819461 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id A8CBCBF440 for ; Thu, 12 Feb 2015 12:47:24 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D48292011D for ; Thu, 12 Feb 2015 12:47:23 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0A61620103 for ; Thu, 12 Feb 2015 12:47:23 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YLt88-0001Yz-88; Thu, 12 Feb 2015 12:44:28 +0000 Received: from szxga03-in.huawei.com ([119.145.14.66]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YLsu2-0000uh-DJ; Thu, 12 Feb 2015 12:29:55 +0000 Received: from 172.24.2.119 (EHLO lggeml425-hub.china.huawei.com) ([172.24.2.119]) by szxrg03-dlp.huawei.com (MOS 4.4.3-GA FastPath queued) with ESMTP id BBV91937; Thu, 12 Feb 2015 20:28:01 +0800 (CST) Received: from kernel-host.huawei (10.107.197.247) by lggeml425-hub.china.huawei.com (10.72.61.35) with Microsoft SMTP Server id 14.3.158.1; Thu, 12 Feb 2015 20:27:55 +0800 From: Wang Nan To: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [RFC PATCH v2 22/26] early kprobes: introduce arch_fix_ftrace_early_kprobe(). Date: Thu, 12 Feb 2015 20:21:15 +0800 Message-ID: <1423743675-12986-1-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.4 In-Reply-To: <1423743476-11927-1-git-send-email-wangnan0@huawei.com> References: <1423743476-11927-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.107.197.247] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.54DC9C51.0249, ss=1, re=0.001, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 394ec886f411b3fee5f373da0336a4a0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150212_042954_856273_261FBBC1 X-CRM114-Status: UNSURE ( 9.48 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.3 (--) Cc: lizefan@huawei.com, x86@kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Gives arch code a chance to fix ftrace entry. Signed-off-by: Wang Nan --- arch/x86/kernel/kprobes/opt.c | 31 +++++++++++++++++++++++++++++++ include/linux/kprobes.h | 6 +++++- kernel/kprobes.c | 6 ++++++ 3 files changed, 42 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index 21847ab..f3ea954 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -456,3 +456,34 @@ int setup_detour_execution(struct kprobe *p, struct pt_regs *regs, int reenter) return 0; } NOKPROBE_SYMBOL(setup_detour_execution); + +#ifdef CONFIG_EARLY_KPROBES +void arch_fix_ftrace_early_kprobe(struct optimized_kprobe *op) +{ + const unsigned char *correct_nop5 = ideal_nops[NOP_ATOMIC5]; + struct kprobe *list_p; + + u32 mask = KPROBE_FLAG_EARLY | + KPROBE_FLAG_OPTIMIZED | + KPROBE_FLAG_FTRACE; + + if ((op->kp.flags & mask) != mask) + return; + + /* + * For early kprobe on ftrace, use right nop instruction. + * See x86 ftrace_make_nop and ftrace_nop_replace. Note that + * ideal_nops used by ftrace_nop_replace is setupt after early + * kprobe registration. + */ + + memcpy(&op->kp.opcode, correct_nop5, sizeof(kprobe_opcode_t)); + memcpy(op->optinsn.copied_insn, correct_nop5 + INT3_SIZE, + RELATIVE_ADDR_SIZE); + + /* Fix all kprobes connected to it */ + list_for_each_entry_rcu(list_p, &op->kp.list, list) + memcpy(&list_p->opcode, correct_nop5, sizeof(kprobe_opcode_t)); + +} +#endif diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index 0c64df8..990d04b 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -330,7 +330,6 @@ extern kprobe_opcode_t __early_kprobes_code_area_start[]; extern kprobe_opcode_t __early_kprobes_code_area_end[]; extern kprobe_opcode_t __early_kprobes_insn_slot_start[]; extern kprobe_opcode_t __early_kprobes_insn_slot_end[]; - #else #define __DEFINE_EKPROBE_ALLOC_OPS(__t, __name) \ static inline __t *__ek_alloc_##__name(__t *__s, __t *__e, unsigned long *__b)\ @@ -459,6 +458,11 @@ struct early_kprobe_slot { extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs); extern int arch_prepare_kprobe_ftrace(struct kprobe *p); + +#ifdef CONFIG_EARLY_KPROBES +extern void arch_fix_ftrace_early_kprobe(struct optimized_kprobe *p); +#endif + #endif int arch_check_ftrace_location(struct kprobe *p); diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 131a71a..0bbb510 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -2536,6 +2536,12 @@ EXPORT_SYMBOL_GPL(jprobe_return); #ifdef CONFIG_EARLY_KPROBES +#ifdef CONFIG_KPROBES_ON_FTRACE +void __weak arch_fix_ftrace_early_kprobe(struct optimized_kprobe *p) +{ +} +#endif + static int register_early_kprobe(struct kprobe *p) { struct early_kprobe_slot *slot;